How is a flag used inside it's country

Which objects allow humans to access groundwater? check all that apply.

The point where two air masses meet is called a

Look at the diagram showing the different wavelengths in sunlight. which statement describes electromagnetic waves with wavelengths greater than 700 nanometers? they take the form of heat. they can cause skin cancer and sunburn. they are some of the shortest waves. they can be seen by human eyes as visible light.